v3.25.2
Short-term Investments and Fair Value Measurements
 6 Months Ended
Jun. 30, 2025
Investments, Debt and Equity Securities [Abstract]  
Short-term Investments and Fair Value Measurements Short-term Investments and Fair Value Measurements
The following is a summary of available-for-sale securities as of June 30, 2025 and December 31, 2024:
 As of June 30, 2025
 Contractual
Maturity (in years)		CostGross Unrealized
Gains		Gross Unrealized
Losses		Fair Market Value
Mutual funds---$14,984,750 $— $(546,183)$14,438,567 
U.S. treasury securities
Less than 1
4,956,858 692 — 4,957,550 
Certificates of deposit
Less than 1
2,980,944 8,781 (271)2,989,454 
U.S. agency mortgage-backed securities*1,220,459 — (407,947)812,512 
$24,143,011 $9,473 $(954,401)$23,198,083 
 As of December 31, 2024
Contractual
Maturity (in years)		CostGross Unrealized
Gains		Gross Unrealized
Losses		Fair Market Value
Mutual funds---$25,926,415 $— $(1,445,706)$24,480,709 
Certificates of deposit
Less than 1
2,980,273 9,750 (281)2,989,742 
U.S. agency mortgage-backed securities*1,260,745 — (430,964)829,781 
$30,167,433 $9,750 $(1,876,951)$28,300,232 
*No single maturity date.
During the three and six months ended June 30, 2025, the Company recorded gross realized gains on investments of $300 and $500, respectively, and gross realized losses on investments of $708,000 and $709,000, respectively. During the three and six months ended June 30, 2024, the Company recorded gross realized gains on investments of $300 and $500, respectively, and gross realized losses on investments of $2,000 and $693,000, respectively. During the three and six months ended June 30, 2025, the Company recorded net unrealized gains on available-for-sale equity securities of $759,000 and $900,000, respectively. During the three and six months ended June 30, 2024, the Company recorded net unrealized (loss) gain on available-for-sale equity securities of $(21,000) and $480,000, respectively. No material balances were reclassified out of accumulated other comprehensive loss for the three and six months ended June 30, 2025 and 2024. Interest and dividends on investments classified as available-for-sale are included in interest income in the condensed consolidated statements of
operations. As of June 30, 2025, the Company had 12 available-for-sale securities with an aggregate total unrealized loss of $954,000. All of these securities had been in a loss position for longer than 12 months as of June 30, 2025.
The Company periodically reviews its portfolio of available-for-sale debt securities to determine if any investment is impaired due to credit loss or other potential valuation concerns. For the debt securities where the fair value of the investment is less than the amortized cost basis, the Company has assessed at the individual security level for various quantitative factors including, but not limited to, the nature of the investments, changes in credit ratings, interest rate fluctuations, industry analyst reports, and the severity of impairment. Unrealized losses on available-for-sale debt securities as of June 30, 2025 were primarily due to changes in interest rates, and not due to increased credit risks associated with specific securities. Based on the credit quality of the available-for-sale debt securities that are in an unrealized loss position, and the Company’s estimates of future cash flows to be collected from those securities, the Company believes the unrealized losses are not credit losses. Accordingly, at June 30, 2025, the Company has not recorded an allowance for credit losses related to its available-for-sale debt securities.
The following table presents the Company’s assets that were measured at fair value on a recurring basis, determined using the following inputs as of June 30, 2025:

Fair Value Measurements at
 June 30, 2025
 TotalQuoted Prices
in Active Markets
(Level 1)		Significant
Other Unobservable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)
Assets:
Short-term investments
     Mutual funds$14,438,567 $14,438,567 $— $— 
     U.S. treasury securities4,957,550 4,957,550 — — 
     Certificates of deposit2,989,454 — 2,989,454 — 
     U.S. agency mortgage-backed securities812,512 — 812,512 — 
Total short-term investments23,198,083 19,396,117 3,801,966 — 
Investment in affiliated entity3,085,348 3,085,348 — — 
Total assets measured at fair value$26,283,431 $22,481,465 $3,801,966 $— 
Liabilities:
Common stock warrant liability11,420,326 $— $— 11,420,326 
Total liabilities$11,420,326 $— $— $11,420,326 

The following table presents the Company’s assets that were measured at fair value on a recurring basis, determined using the following inputs as of December 31, 2024:
Fair Value Measurements at
 December 31, 2024
 TotalQuoted Prices
in Active Markets
(Level 1)		Significant
Other Unobservable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)
Assets:
Short-term investments
     Mutual funds$24,480,709 $24,480,709 $— $— 
     Certificates of deposit2,989,742 — 2,989,742 — 
     U.S. agency mortgage-backed securities829,781 — 829,781 — 
Total short-term investments28,300,232 24,480,709 3,819,523 — 
Investment in affiliated entity1,613,844 1,613,844 — — 
Total assets measured at fair value$29,914,076 $26,094,553 $3,819,523 $— 
Liabilities:
Common stock warrant liability13,255,188 — — 13,255,188 
Total liabilities$13,255,188 $— $— $13,255,188 

Level 1 assets at June 30, 2025 consisted of mutual funds, U.S. treasury securities and the Company’s investment in its affiliated entity, Plumbline Life Sciences, Inc. (“PLS”). See Note 10 for additional information. The Company accounts for its investment in 597,808 common shares of PLS based on the closing price of the shares on the Korea New Exchange Market on the applicable balance sheet date. Unrealized gains and losses on the Company's equity securities are reported in the consolidated statement of operations as unrealized gain or loss on available-for-sale equity securities or as a gain or loss on investment in affiliated entity.
Level 2 assets at June 30, 2025 consisted of certificates of deposit and U.S. agency mortgage-backed securities held by the Company that are initially valued at the transaction price and subsequently valued, at the end of each reporting period, typically utilizing market observable data. The Company obtains the fair value of its Level 2 assets from a professional pricing service, which may use quoted market prices for identical or comparable instruments, or inputs other than quoted prices that are observable either directly or indirectly. The professional pricing service gathers quoted market prices and observable inputs from a variety of industry data providers. The valuation techniques used to measure the fair value of the Company's Level 2 financial instruments were derived from non-binding market consensus prices that are corroborated by observable market data, quoted market prices for similar instruments, or pricing models such as discounted cash flow techniques. The Company validates the quoted market prices provided by the primary pricing service by comparing the service's assessment of the fair values of the Company's investment portfolio balance against the fair values of the Company's investment portfolio balance obtained from an independent source.
There were no Level 3 assets held as of June 30, 2025 or December 31, 2024.
Level 3 liabilities held as of June 30, 2025 and December 31, 2024 consisted of liabilities associated with the Warrants to purchase common stock issued in the Company's underwritten public offering that closed in December 2024. See Note 7 for additional information about the liability-classified warrants.
The Company reassesses the fair value of the common stock warrant liability at each reporting date utilizing a Black-Scholes pricing model. The following assumptions were used to estimate the fair value of the warrant liability:

June 30, 2025December 31, 2024
Risk-free interest rate3.7%4.4%
Expected volatility87%111%
Expected life in years4.55
Dividend yield——

Changes in these assumptions as well as fluctuations in the Company's stock price between the valuation dates can have a
significant impact on the fair value of the common stock warrant liability. Expected volatility was based on historical volatility. Historical volatility was computed using daily pricing observations for recent periods. The Company believes this method produced an estimate that was representative of the Company’s expectations of future volatility over the expected term.
Expected term is calculated based on the remaining contractual term of the Warrants. The risk-free rate was based on the U.S. Treasury rate that corresponds to the expected term of the Warrants. As a result of these calculations, the Company recorded an increase (decrease) in fair value of the liability of $1.9 million and $(1.8) million on the condensed consolidated statement of operations for the three and six months ended June 30, 2025, respectively.
The following table presents the change in fair value of the Company’s total Level 3 financial liabilities for the six months ended June 30, 2025:
Common Stock Warrant Liability
Balance at December 31, 202413,255,188 
Decrease in fair value of liability(1,834,862)
Balance at June 30, 2025$11,420,326 
Short-term Investments and Fair Value Measurements Short-term Investments and Fair Value Measurements
The following is a summary of available-for-sale securities as of June 30, 2025 and December 31, 2024:
 As of June 30, 2025
 Contractual
Maturity (in years)		CostGross Unrealized
Gains		Gross Unrealized
Losses		Fair Market Value
Mutual funds---$14,984,750 $— $(546,183)$14,438,567 
U.S. treasury securities
Less than 1
4,956,858 692 — 4,957,550 
Certificates of deposit
Less than 1
2,980,944 8,781 (271)2,989,454 
U.S. agency mortgage-backed securities*1,220,459 — (407,947)812,512 
$24,143,011 $9,473 $(954,401)$23,198,083 
 As of December 31, 2024
Contractual
Maturity (in years)		CostGross Unrealized
Gains		Gross Unrealized
Losses		Fair Market Value
Mutual funds---$25,926,415 $— $(1,445,706)$24,480,709 
Certificates of deposit
Less than 1
2,980,273 9,750 (281)2,989,742 
U.S. agency mortgage-backed securities*1,260,745 — (430,964)829,781 
$30,167,433 $9,750 $(1,876,951)$28,300,232 
*No single maturity date.
During the three and six months ended June 30, 2025, the Company recorded gross realized gains on investments of $300 and $500, respectively, and gross realized losses on investments of $708,000 and $709,000, respectively. During the three and six months ended June 30, 2024, the Company recorded gross realized gains on investments of $300 and $500, respectively, and gross realized losses on investments of $2,000 and $693,000, respectively. During the three and six months ended June 30, 2025, the Company recorded net unrealized gains on available-for-sale equity securities of $759,000 and $900,000, respectively. During the three and six months ended June 30, 2024, the Company recorded net unrealized (loss) gain on available-for-sale equity securities of $(21,000) and $480,000, respectively. No material balances were reclassified out of accumulated other comprehensive loss for the three and six months ended June 30, 2025 and 2024. Interest and dividends on investments classified as available-for-sale are included in interest income in the condensed consolidated statements of
operations. As of June 30, 2025, the Company had 12 available-for-sale securities with an aggregate total unrealized loss of $954,000. All of these securities had been in a loss position for longer than 12 months as of June 30, 2025.
The Company periodically reviews its portfolio of available-for-sale debt securities to determine if any investment is impaired due to credit loss or other potential valuation concerns. For the debt securities where the fair value of the investment is less than the amortized cost basis, the Company has assessed at the individual security level for various quantitative factors including, but not limited to, the nature of the investments, changes in credit ratings, interest rate fluctuations, industry analyst reports, and the severity of impairment. Unrealized losses on available-for-sale debt securities as of June 30, 2025 were primarily due to changes in interest rates, and not due to increased credit risks associated with specific securities. Based on the credit quality of the available-for-sale debt securities that are in an unrealized loss position, and the Company’s estimates of future cash flows to be collected from those securities, the Company believes the unrealized losses are not credit losses. Accordingly, at June 30, 2025, the Company has not recorded an allowance for credit losses related to its available-for-sale debt securities.
The following table presents the Company’s assets that were measured at fair value on a recurring basis, determined using the following inputs as of June 30, 2025:

Fair Value Measurements at
 June 30, 2025
 TotalQuoted Prices
in Active Markets
(Level 1)		Significant
Other Unobservable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)
Assets:
Short-term investments
     Mutual funds$14,438,567 $14,438,567 $— $— 
     U.S. treasury securities4,957,550 4,957,550 — — 
     Certificates of deposit2,989,454 — 2,989,454 — 
     U.S. agency mortgage-backed securities812,512 — 812,512 — 
Total short-term investments23,198,083 19,396,117 3,801,966 — 
Investment in affiliated entity3,085,348 3,085,348 — — 
Total assets measured at fair value$26,283,431 $22,481,465 $3,801,966 $— 
Liabilities:
Common stock warrant liability11,420,326 $— $— 11,420,326 
Total liabilities$11,420,326 $— $— $11,420,326 

The following table presents the Company’s assets that were measured at fair value on a recurring basis, determined using the following inputs as of December 31, 2024:
Fair Value Measurements at
 December 31, 2024
 TotalQuoted Prices
in Active Markets
(Level 1)		Significant
Other Unobservable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)
Assets:
Short-term investments
     Mutual funds$24,480,709 $24,480,709 $— $— 
     Certificates of deposit2,989,742 — 2,989,742 — 
     U.S. agency mortgage-backed securities829,781 — 829,781 — 
Total short-term investments28,300,232 24,480,709 3,819,523 — 
Investment in affiliated entity1,613,844 1,613,844 — — 
Total assets measured at fair value$29,914,076 $26,094,553 $3,819,523 $— 
Liabilities:
Common stock warrant liability13,255,188 — — 13,255,188 
Total liabilities$13,255,188 $— $— $13,255,188 

Level 1 assets at June 30, 2025 consisted of mutual funds, U.S. treasury securities and the Company’s investment in its affiliated entity, Plumbline Life Sciences, Inc. (“PLS”). See Note 10 for additional information. The Company accounts for its investment in 597,808 common shares of PLS based on the closing price of the shares on the Korea New Exchange Market on the applicable balance sheet date. Unrealized gains and losses on the Company's equity securities are reported in the consolidated statement of operations as unrealized gain or loss on available-for-sale equity securities or as a gain or loss on investment in affiliated entity.
Level 2 assets at June 30, 2025 consisted of certificates of deposit and U.S. agency mortgage-backed securities held by the Company that are initially valued at the transaction price and subsequently valued, at the end of each reporting period, typically utilizing market observable data. The Company obtains the fair value of its Level 2 assets from a professional pricing service, which may use quoted market prices for identical or comparable instruments, or inputs other than quoted prices that are observable either directly or indirectly. The professional pricing service gathers quoted market prices and observable inputs from a variety of industry data providers. The valuation techniques used to measure the fair value of the Company's Level 2 financial instruments were derived from non-binding market consensus prices that are corroborated by observable market data, quoted market prices for similar instruments, or pricing models such as discounted cash flow techniques. The Company validates the quoted market prices provided by the primary pricing service by comparing the service's assessment of the fair values of the Company's investment portfolio balance against the fair values of the Company's investment portfolio balance obtained from an independent source.
There were no Level 3 assets held as of June 30, 2025 or December 31, 2024.
Level 3 liabilities held as of June 30, 2025 and December 31, 2024 consisted of liabilities associated with the Warrants to purchase common stock issued in the Company's underwritten public offering that closed in December 2024. See Note 7 for additional information about the liability-classified warrants.
The Company reassesses the fair value of the common stock warrant liability at each reporting date utilizing a Black-Scholes pricing model. The following assumptions were used to estimate the fair value of the warrant liability:

June 30, 2025December 31, 2024
Risk-free interest rate3.7%4.4%
Expected volatility87%111%
Expected life in years4.55
Dividend yield——

Changes in these assumptions as well as fluctuations in the Company's stock price between the valuation dates can have a
significant impact on the fair value of the common stock warrant liability. Expected volatility was based on historical volatility. Historical volatility was computed using daily pricing observations for recent periods. The Company believes this method produced an estimate that was representative of the Company’s expectations of future volatility over the expected term.
Expected term is calculated based on the remaining contractual term of the Warrants. The risk-free rate was based on the U.S. Treasury rate that corresponds to the expected term of the Warrants. As a result of these calculations, the Company recorded an increase (decrease) in fair value of the liability of $1.9 million and $(1.8) million on the condensed consolidated statement of operations for the three and six months ended June 30, 2025, respectively.
The following table presents the change in fair value of the Company’s total Level 3 financial liabilities for the six months ended June 30, 2025:
Common Stock Warrant Liability
Balance at December 31, 202413,255,188 
Decrease in fair value of liability(1,834,862)
Balance at June 30, 2025$11,420,326